1. Field of the Invention
The present invention relates to a computer program product, system, and method for processing requests for services in a service request at a receiving controller and processing controller in a switch.
2. Description of the Related Art
A distributed switch includes a plurality of interconnected forwarders that provide ports to interconnect device nodes. In a distributed Fibre Channel over Ethernet (FCoE) forwarder, a controlling FCoE forwarder (cFCF) is in communication with one or more FCoE data forwarders (FDFs) over an Ethernet network. The cFCF and connected FDFs provide Fibre Channel connections to device nodes in a Fibre Channel Fabric.
Distributed switches separate the control and data forwarding aspects of a Fibre Channel Switch into separate elements called Controlling Switches (cSW), also referred to as controlling forwarders, and Fibre Channel Data Forwarders (FCDFs). Controlling Switches (controlling forwarders) and FCDFs are interconnected through Fibre Channel links or Lossless Ethernet fabrics in the case of FCoE. The technology allows for centralized control and management of the SAN in the controlling switch, and localized switching and forwarding of data between devices connected to the FCDFs without having to traverse the core of the fabric (the controlling switch).
A distributed switch is also referred to as a Virtual Domain as it virtualizes the existence of a Fibre Channel switch which provides a Fibre Channel Domain in the SAN.
A distributed switch provides separation of the entities that provide Fibre Channel services to the end devices. The F_Port Controller resides in the FCDFs and other services remain in the controlling switch (Fabric controller, Domain Controller, Name Server, etc). The Fibre Channel Link Services standard provides a set of Extended Link Services (ELS) that are used by end devices (such as servers or storage devices) to operate within the SAN and to provide information to upper level services or applications for management of the devices in the SAN. Some of these Link Services are provided by the F_Port Controller, and others are provided by the fabric controller, name server or the domain controller in the controlling forwarder. An ELS request is addressed specifically to the provider of the service as indicated in the addressing specification for each of the link services.